LONDON – The British government on Thursday gave the go-ahead for a Chinese-financed nuclear power station, two months after Prime Minister Theresa May balked at a deal that has raised concerns about the security of Britain’s energy supply.

The proposed £18 billion ($31 billion) nuclear plant, known as Hinkley Point C, will be the first built in Britain in decades. David Cameron, the former prime minister, had pushed hard for the project during his tenure, touting it as a critical source of low-carbon energy and as evidence of a new “golden era” in British relations with China.

But days after May took over from Cameron in July following his failed campaign to keep Britain in the European Union, she stunned observers by announcing a fresh review of the plan’s details just hours before she was expected to sign off on it.

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The pause interrupted plans for a lavish garden party thrown by the project’s French backers. But more importantly, it called into question whether the new prime minister would ever allow Hinkley Point to go ahead.

China responded with veiled threats that scuttling the project would endanger the countries’ growing ties.

On Thursday, Downing Street announced that the project would proceed, but with new conditions.

“Following a comprehensive review of the Hinkley Point C project, and a revised agreement with (French energy giant) EDF, the government has decided to proceed with the first new nuclear power station for a generation,” said a government statement issued Thursday morning. “However, ministers will impose a new legal framework for future foreign investment in Britain’s critical infrastructure, which will include nuclear energy and apply after Hinkley.”

The plan has drawn fierce criticism, both because of its eye-watering cost and because of concerns that giving China a stake in Britain’s energy infrastructure leaves Britain vulnerable to a country whose geostrategic interests are hardly aligned with its own.

May’s own chief of staff, Nick Timothy, wrote last year that “the Chinese could use their role to build weaknesses into computer systems which will allow them to shut down Britain’s energy production at will.”

But whatever the reservations of May and her team, Hinkley Point may have been too far along in the planning by the time she took office for her to cancel the project.

China is an investor in Hinkley Point, not the builder. That task has been left to the French, with the Chinese kicking in a third of the cost.

The Chinese could use their role to build weaknesses into computer systems which will allow them to shut down Britain’s energy production at will

But the state-controlled China General Nuclear Power Group has long regarded Hinkley Point as just the start of its investment in Britain. Two other plants are in the planning stages, and are linked to the Hinkley Point deal. One is expected to be Chinese-led and designed.

The conditions attached to the deal on Thursday raise questions about how plans for the two next plants will proceed. Downing Street’s statement promised “reforms to the government’s approach to the ownership and control of critical infrastructure to ensure that the full implications of foreign ownership are scrutinized for the purposes of national security.”

May is said by colleagues to be more hawkish on China than was Cameron or his top finance official, George Osborne, who led the push for closer ties with Beijing. Before taking the keys to 10 Downing Street, May was responsible for Britain’s internal security as the country’s home secretary.

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Labour groups both in Britain and France had pushed for Hinkley Point to go ahead, citing the potential job creation for such a mammoth project.

But environmental groups have been sharply critical of the deal. British Green Party co-leader called Hinkley Point “a white elephant” and called for the government to invest instead in “offshore wind, energy efficiency and innovative new technologies such as energy storage.”

The Hinkley Point facility will be built in the British county of Somerset, on the southwestern coast. The plant is due to be completed by 2025, although experts say that timetable may be unrealistic given a track record of delays on other major nuclear projects.